A. Field of the Invention
The invention is an apparatus and method for applying force to an object orthogonal to the direction of an oscillating movement of air. As used in this document, the term ‘oscillating’ means that the air moves in a first direction followed by movement of the air in the opposite direction. A sound wave is an example of oscillating air. As used in this document, the term ‘orthosonic’ means perpendicular to the direction of the oscillating movement of air. For a propagating sound wave, the term ‘orthosonic’ means perpendicular to the direction of propagation of the sound wave. As used in this document, the term ‘air’ means atmospheric air and also means any gas or liquid.
B. Description of the Related Art
Aerodynamic lift is generated by movement of air with respect to a surface due to the well-known Bernoulli principle. According to the Bernoulli principle, the difference in static pressure, transverse to the direction of flow of air at two locations, is proportional to the difference in the squares of the velocity of the air at the two locations. A necessary corollary to the Bernoulli principle is that the air motion important to affect the static pressure at a surface is relative air motion between the surface and the air—either the air, the surface or both can be moving. Also, the location of the moving air that affects the static pressure at the surface is in the boundary layer immediately adjacent to the surface, since only air molecules that come in contact with the surface can apply pressure to the surface. Finally, the relation between velocity and static pressure is instantaneous. A change in velocity instantly causes a change in static pressure.
From the Bernoulli principle and all other things being equal, the faster the movement of air in the boundary layer parallel to the surface, the lower the static pressure exerted by the air against the surface.
In a prior art wing, air moves in only one direction, from the leading edge of the wing to the trailing edge. In the case of an aircraft wing, air is moving faster adjacent to the top surface of the wing than adjacent to the bottom surface of the wing. The air exerts a lower static pressure on the wing top surface than on the wing bottom surface. The difference in the static pressure on the wing top surface and the wing bottom surface results in lift.
The nature of fluid flow affects the operation of a conventional wing; namely, turbulence and drag. The flow of air beyond a critical distance or for longer than a critical time results in the flow becoming turbulent. Turbulent flow is chaotic and results in loss of lift and higher drag and subsequently increased power to maintain the velocity of the air with respect to the wing. In a conventional wing with air flow in only one direction, turbulence is unavoidable because the critical distance and time are exceeded by the one-way flow of air.
A ‘Bernoulli grip’ is a specialized case of a conventional wing. In a Bernoulli grip, air flows from an orifice on a gripping member. When the gripping member is moved into close proximity to the surface of an object, the air flowing from the gripping member moves radially away from the orifice between the surface of the object and a corresponding gripping member surface. The air is exhausted at the edges of the corresponding surfaces of the gripping member and object. From the Bernoulli principle, the velocity of the air as it moves across the gripping member causes the static pressure between the surfaces of the object and the gripping member to be reduced proportional to the square of the air velocity. The side of the object opposite to the gripping member experiences an air velocity of zero and the static pressure is the same as the ambient air pressure. The net force due to the differences in air pressure acting on the object urges the object toward the gripping member. The lifting power of the Bernoulli grip is reduced because the discharge of air from the orifice causes a local increase in air pressure in the vicinity of the nozzle due to the momentum of the moving air against the surface of the object, which reduces the net force urging the object toward the gripping member.
The prior art does not teach the apparatus or method of the invention.